Designing Tunable Paper-Based Colorimetric Sensor for Precise Detection of Hydrogen Peroxide Vapor.

Detection of hydrogen peroxide (HO) vapor remains a significant challenge for conventional sensing technologies, despite its significance in applications such as the detection of improvised explosive devices (IEDs). Herein, we report a novel, highly sensitive colorimetric sensor system capable of detecting HO vapor at concentrations as low as parts-per-billion (ppb). The sensor is based on a cellulose microfibril network, derived from paper towels, which provides a versatile and tunable substrate for the incorporation of Ti-(IV) oxo complexes.

Application of Nanoconfinement Technology for Highly Effective Monitoring of Chemical Exposure During Military Service.

Introduction: There is myriad of volatile compounds to which military personnel are exposed that can potentially have negative effects on their health. Military service occurs in a broad array of environments so it is difficult to predict the hazardous compounds to which the personnel might be exposed. XploSafe is developing passive diffusive samplers to facilitate the sampling and quantification of a wide range of chemical vapor exposures that personnel may be exposed to in the workplace.

Detection of Hydrogen Peroxide in Liquid and Vapors Using Titanium(IV)-Based Test Strips and Low-Cost Hardware.

Titanium(IV) solutions are known to detect hydrogen peroxide in solutions by a colorimetric method. Xplosafe's XploSens PS commercial titanium(IV)-based peroxide detection test strips are used to detect hydrogen peroxide in liquids. The use of these test strips as gas-phase detectors for peroxides was tested using low-cost hardware.

Superior Monitoring of Chemical Exposure Using Nanoconfinement Technology.

Introduction: Military personnel are exposed to a broad range of potentially toxic compounds that can affect their health. These hazards are unpredictable because military service occurs in a wide array of uncontrolled environments. Therefore, a novel sorbent was developed that allows the fabrication of lightweight personal samplers that are both capable of sorbing an extremely wide range of organic chemical types and able to stabilize reactive compounds.

Crystal structure of melaminium cyano-acetate monohydrate.

The asymmetric unit of the title compound, 2,4,6-tri-amino-1,3,5-triazin-1-ium cyano-acetate monohydrate, CHN ·NCCHCOO·HO, consists of a melaminium cation, a cyano-acetate anion and a water mol-ecule, which are connected to each other N-H⋯O and O-H⋯O hydrogen bonds, generating an eight-membered ring. In the crystal, the melaminium cations are connected by two pairs of N-H⋯N hydrogen bonds, forming tapes along [110]. These tapes develop a three-dimensional network through N-H⋯O, O-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds between the cations, anions and water mol-ecules.

Methods for the reaction of alkenes with activated tungstic acid.

In this study, we have synthesized activated tungstic acid by dehydration of tungstic acid as a highly efficient catalyst and employed it for the catalytic transformations of various alkenes. The importance of this series of studies is to help students to graphically visualize a diverse array of organic synthesis reactions. The alkenes react differently depending on their structure via mainly acid-catalyzed reactions that produce a whole range of products including coupled products (dimers).

Catalytic co-pyrolysis of red cedar with methane to produce upgraded bio-oil.

Fast pyrolysis is a promising route to transform biomass into bio-oil for further refining into transportation fuels and chemicals. However, bio-oil applications suffer from several challenges due to its adverse properties. This study reports improving bio-oil properties through co-pyrolysis of biomass with methane over molybdenum/zinc (MoZn/ZHSM-5) and HZSM-5 catalysts that promote deoxygenation, decarbonylation, hydrogen transfer and aromatization reactions.

Titania-hydroxypropyl cellulose thin films for the detection of peroxide vapors.

Titania nanoparticles in a hydroxypropyl cellulose matrix produced using a sol-gel method were utilized to prepare films on polycarbonate slides and coatings on cellulose papers. The exposure of these materials to hydrogen peroxide gas leads to the development of an intense yellow color. By using an inexpensive web camera and a tungsten lamp to measure the reflected light, first-order behavior in the color change was observed when exposed to peroxide vapor of less than 50 ppm.

Remediation of arsenic and lead with nanocrystalline zinc sulfide.

Nanocrystalline (1.7 ± 0.3 nm) zinc sulfide with a specific surface area up to 360 m(2) g(-1) was prepared from the thermal decomposition of a single-source precursor, zinc ethylxanthate.

Iron-rich Oklahoma clays as a natural source of chromium in monitoring wells.

Water samples, drawn from groundwater monitoring wells located southeast of Oklahoma City, OK, were found to contain elevated concentrations of total chromium with an apparent source localized to the area surrounding each well. Since these monitoring wells are located in areas with no historic chromium usage, industrial sources of chromium were ruled out. Water testing was performed on twelve monitoring wells in the area that historically had elevated total chromium concentrations ranging from 10-4900 micrograms per litre.

Follow-up study on the effects on well chemistry from biological and chemical remediation of chlorinated solvents.

The enduring effects of injected materials used for the remediation of chlorinated solvents were examined. Approximately two years previous to this study, four different remediation methods were tested in an area located southeast of Oklahoma City, OK. These methods included bioremediation under both anaerobic and aerobic conditions and chemical remediation using Fenton's reagent or KMnO(4).

Metal ion adsorption using polyamine-functionalized mesoporous materials prepared from bromopropyl-functionalized mesoporous silica.

Mesoporous silicas carrying di-, tri-, or penta-amine functional groups were prepared by prior functionalization of a mesoporous silica with bromopropyl-functional groups followed by nucleophilic displacement of the bromine atoms by ethylenediamine, diethylenetriamine, or tetraethylenepentamine, respectively. A synthetic method was developed that gave a starting material with very high surface coverage by the 3-brompropyl groups. Batch tests were conducted to investigate the capabilities of the prepared adsorbents for the removal of copper, zinc, and cadmium from aqueous solutions.